Display screen or portion thereof with a graphical user interface input selector



FIG. 1 is a front view of a display screen or portion thereof with agraphical user interface input selector; and,

FIG. 2 is a second embodiment thereof.

The broken lines showing a display screen or portion thereof andelements of the graphical user interface illustrate portions of thearticle and form no part of the claimed design.

CLAIM The ornamental design for a display screen or portion thereof witha graphical user interface input selector, as shown and described.